Phase unwrapping Assume that we have two signals taken at different times: g 1 = a 1 exp(i4  R 1 / ) g 2 = a 2 exp(i4  R 2 / ) a1,a2 = complex reflectivity R1, R2 is range from antenna to surface = wavelength At a given point, assume a 1 = a 2 = a (g1)(g2*) = (a 2 )exp[i4  (R 1 -R 2 )] = s(t) The phase of this function is proportional to the effective difference in range, which in turn depends on satellite geometry, topography, soil moisture, or maybe even deformation.
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